On the 2003, if you buy Motorcraft plugs you should not use anti-seize on the threads, or if you do, use very very little. The Motorcraft plugs have nickel plated threads and using anti-seize (or too much) is part of the reason why these engines pop-out spark plugs.
I bought a 2003 used, it had a ticking noise which was a result of this very thing. One of the plugs was loose because the previous owner changed the plugs and used plenty of anti-seize.
I did use the Motorcraft plugs and I did use anti-seize but only a tiny bit.
Edit: other tune up items:
1: I didn't change the coil packs but I did clean the boots and springs and use dielectric grease.
2: Changed all the filters: Oil, air, PCV, fuel, transmission filter
3: Changed all the fluids: Coolant, oil, transfer, transmission, Diff (with friction modifier to keep my LSD from chattering), bled the brakes.
4: I inspected everything but my rig doesn't have serviceable joints (no zerk fittings) and the bearings, ball joints and tie rods all felt healthy with no play.